Author Topic: Rear brake drum swap  (Read 1584 times)

Shawn

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Rear brake drum swap
« on: December 03, 2022, 12:14:06 PM »
I have a 1969 9" rear with 10x1/34 drums.  Can I swap them out for 10x2" drums?  Will the backing plate accept this change?

Bob Gaines

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Re: Rear brake drum swap
« Reply #1 on: December 03, 2022, 12:57:56 PM »
I have a 1969 9" rear with 10x1/34 drums.  Can I swap them out for 10x2" drums?  Will the backing plate accept this change?
Why would you want to and risk clearance issues with the backing plate? It is not like you can add 2"shoes to the stock backing plates for more braking. They commomly available aftermarket or the 10X 1 3/4 was on over a million cars over the years so there are still a lot of donor application options still available.
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

jamesfee

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Re: Rear brake drum swap
« Reply #2 on: December 03, 2022, 03:04:40 PM »
Shawn,

IDK about the backing plate/drum change (I've got a '66) but if you are looking for a driveability work-around I would look into some of the more aggressive friction compounds. I'm running Porterfield's R-4 compound but I'm sure there are several other brands as well that will give you better braking with the setup you already have. Just a thought.

j
6S1801

Shawn

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Re: Rear brake drum swap
« Reply #3 on: December 03, 2022, 06:41:48 PM »
I guess what I'm asking is can the original backing plates stay and use 2" drums?  The 1 3/4 drums are trash and was just looking into using the 2" if possible. Also the rear is a 1967  not 1969

jamesfee

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Re: Rear brake drum swap
« Reply #4 on: December 04, 2022, 01:29:51 PM »
Shawn,

If that's the case, I would see your local parts house guy/girl. FWIW the Rock Auto site lists a 10x2 drum for that year. I would have thought the 390's came with the bigger size - but you need a reliable way to research that.

jim
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Bob Gaines

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Re: Rear brake drum swap
« Reply #5 on: December 04, 2022, 01:36:11 PM »
Shawn,

If that's the case, I would see your local parts house guy/girl. FWIW the Rock Auto site lists a 10x2 drum for that year. I would have thought the 390's came with the bigger size - but you need a reliable way to research that.

jim
Both 67 and 69 390 or even 428 Mustang used 1 3/4 shoes from the factory
« Last Edit: December 04, 2022, 07:27:14 PM by Bob Gaines »
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jamesfee

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Re: Rear brake drum swap
« Reply #6 on: December 04, 2022, 05:22:58 PM »
Thanks for that insight Bob.

j
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Shawn

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Re: Rear brake drum swap
« Reply #7 on: December 05, 2022, 01:42:45 PM »
Thanks All - I may have posted a bit early before taking accurate measurements.  I do have 2" brakes on backing plates 71805 and 71806.  Anyone know what the application make and model they are used on?

 

Appreciate your correspondence

Kind Regards

Shawn